diff options
Diffstat (limited to 'core/vm/address.go')
-rw-r--r-- | core/vm/address.go | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/core/vm/address.go b/core/vm/address.go new file mode 100644 index 000000000..215f4bc8f --- /dev/null +++ b/core/vm/address.go @@ -0,0 +1,77 @@ +package vm + +import ( + "math/big" + + "github.com/ethereum/go-ethereum/crypto" + "github.com/ethereum/go-ethereum/common" +) + +type Address interface { + Call(in []byte) []byte +} + +type PrecompiledAccount struct { + Gas func(l int) *big.Int + fn func(in []byte) []byte +} + +func (self PrecompiledAccount) Call(in []byte) []byte { + return self.fn(in) +} + +var Precompiled = PrecompiledContracts() + +// XXX Could set directly. Testing requires resetting and setting of pre compiled contracts. +func PrecompiledContracts() map[string]*PrecompiledAccount { + return map[string]*PrecompiledAccount{ + // ECRECOVER + string(common.LeftPadBytes([]byte{1}, 20)): &PrecompiledAccount{func(l int) *big.Int { + return GasEcrecover + }, ecrecoverFunc}, + + // SHA256 + string(common.LeftPadBytes([]byte{2}, 20)): &PrecompiledAccount{func(l int) *big.Int { + n := big.NewInt(int64(l+31) / 32) + n.Mul(n, GasSha256Word) + return n.Add(n, GasSha256Base) + }, sha256Func}, + + // RIPEMD160 + string(common.LeftPadBytes([]byte{3}, 20)): &PrecompiledAccount{func(l int) *big.Int { + n := big.NewInt(int64(l+31) / 32) + n.Mul(n, GasRipemdWord) + return n.Add(n, GasRipemdBase) + }, ripemd160Func}, + + string(common.LeftPadBytes([]byte{4}, 20)): &PrecompiledAccount{func(l int) *big.Int { + n := big.NewInt(int64(l+31) / 32) + n.Mul(n, GasIdentityWord) + + return n.Add(n, GasIdentityBase) + }, memCpy}, + } +} + +func sha256Func(in []byte) []byte { + return crypto.Sha256(in) +} + +func ripemd160Func(in []byte) []byte { + return common.LeftPadBytes(crypto.Ripemd160(in), 32) +} + +func ecrecoverFunc(in []byte) []byte { + // In case of an invalid sig. Defaults to return nil + defer func() { recover() }() + + hash := in[:32] + v := common.BigD(in[32:64]).Bytes()[0] - 27 + sig := append(in[64:], v) + + return common.LeftPadBytes(crypto.Sha3(crypto.Ecrecover(append(hash, sig...))[1:])[12:], 32) +} + +func memCpy(in []byte) []byte { + return in +} |